APPENDIX. 751 



healthy blood, and when present in abnormal amount seems to produce 

 rheumatism. 



Oxalatesare present in the urine in certain diseases, and after drink- 

 ing certain carbonated beverages, and after eating rhubarb, etc. 



AKOMATIC SERIES. 



Benzoic, C 7 H 6 0. 



Phenol, C 6 H 6 



Benzoic acid, C 3 H 6 2 , is always found in the urine of herbivora, 

 and can be obtained from stale human urine. It does not exist free else- 

 where. 



Phenol. Phenyl alcohol or carbolic acid exists in minute quantity in 

 human urine. It is an alcohol of the aromatic series. 



2. Inorganic Principles. 



The inorganic proximate principles of the human body are numerous. 

 They are derived, for the most part, directly from food and drink, and 

 pass through the system unaltered. Some are, however, decomposed on 

 their way, as chloride of sodium, of which only four-fifths of the quantity 

 ingested are excreted in the same form; and some are newly formed 

 within the body, as for example, a part of the sulphates and carbonates, 

 and some of the water. 



Much of the inorganic saline matter found in the body is a necessary 

 constituent of its structure, as necessary in its way as albumin or any 

 other organic principle; another partis important in regulating or modi- 

 fying various physical processes, as absorption, solution, and the like; 

 while a part must be reckoned only as matter, which is, so to speak, acci- 

 dentally present, whether derived from the food or the tissues, and which* 

 will, at the first opportunity, be excreted from the body. 



Gases. The gaseous matters found in the body are Oxygen, Hydro- 

 gen, Nitrogen, Carburetted and Sulphuretted hydrogen, and Carbonic 

 acid. The first three have been referred to (p. 732). Carburetted and 

 sulphuretted hydrogen are found in the intestinal canal. Carbonic 

 acid is present in the blood and other fluids, and is excreted in large 

 quantities by the lungs, and in very minute amount by the skin. It 

 has been specially considered in the chapters on Respiration and else- 

 where. 



Water, the most abundant of the proximate principles, forms a large 

 proportion, more than two-thirds of the weight of the whole body. Its 

 relative amount in some of the principal solids and fluids of the body is 

 shown in the following table (quoted by Dalton, from Robin and Ver- 

 irs table, compiled from various authors) : 



